Myocardial infarction is myocardial necrosis due to persistently ischemia of partial myocardium, which results from atheromatous plaque bleeding and intravascular thrombogenesis caused from coronary atherosclerosis, which can result in rapidly, permanently and completely blocking of lumen of the blood vessel, and discontinuing of the bloodstream. It can be divided into 3 phases according to clinical process and ECG manifestation, which are acute, subacute and chronic phases. The clinical symptoms mainly occur in the acute phase, and the highest mortality is in the first week of the acute phase. Acute myocardial infarction (AMI) is common severe case that threatens human life, and it is also currently one of the most harmful heart diseases.
Both experimental and clinical studies domestically and worldwide have found, that some of the myocardial cell will be irreversible infarcted due to AMI, but the surrounding area of the infarcted myocardium remains partially stunning and hibernating, the myocardium were very fragile, which was named as articulo mortis myocardium. Because of presences of different level dysfunction after AMI, the myocardium will be progressed to further necrosis due to calcium overloading, oxygen free radicals damaging or other metabolic factors influences, and will cause further area enlargement of the infarction. (Journal of Jilin University (Medical Edition). 2002, 23 (6): 659-660). The area of myocardial infarction is the major determinant factor of the short and long-term prognosis for AMI patients.